That's BS. Sorry Bob. Not going there with you.
If the reader found out they were talking to a man posing as a three other women authors, all of whom talked to her and each other in a conversation, do you think the reader would be happy? I don't think so.
A rule of thumb my daddy taught me: if you have to hide it, if you have to lie about it, you are probably doing something wrong.
On ads on TV the actors must be identified as such. Think about the "I'm a paid non-doctor spokesperson!" fast-talk at the end of the ad when talking about the wonders of the snake oil they're selling.
There is such a thing as truth in advertising.
Look, I use a pen name. It's my initials plus my mother's maiden name. I used it because when I started writing, I was in a very responsible government job and didn't want people snickering behind their hands when I chaired meetings on very serious matters because they knew I wrote erotic romance.
But I never pretended to be what I was not to my readers. When I use a different pen name, I won't talk to my old one and pretend they're two different people. That's crazy and deceptive.
Sorry if that insults authors who do this kind of thing but that's how I see it. YMMV